The dynamics of a natural system, such as a biological or neural system, modeled by a MES is not directed by a master plan controlling its various CoRegulators (CRs), but modulated by the direct and indirect interactions (through functional loops) between these CRs, each operating at its own complexity level and according to its timescale.

A each time t of the timescale of the MES, the strategies selected on the actual landscapes of the various CRs are relayed to the system with some deformation, via the distortion functor from the landscape to the state-category Kt. All the relayed strategies Si should be realized on Kt for the objectives of the CRs to be fulfilled. In this case, the new state of the system should be represented by the complexification of Kt with respect to a strategy S including the various Si and possibly some global commands imposed by external constraints.

Such a strategy S would be well determined if the commands of the various strategies Si were compatible, as in the case the different CRs are strictly parallel and use independent resources. But it is not the case in a MES in which the CRs are competing for common resources (be they information or energy), so that conflicts may arise between two strategies. Among the causes of incompatibility, let us mention:

• conflict between two strategies using simultaneously a same object for two different functions (an object cannot be at two different locations at the same time);

• lack of coordination between two CRs if the commands of the strategy of the first depend on the choice by the second of a particular strategy, which is not the one it has selected;

• direct or indirect imposition of a strategy by another CR.

The result is that there might exist no strategy S integrating all the commands relayed by the different CRs, and in this case the strategy effectively realized on Kt will be the result of an equilibration process, called the interplay among strategies, through competition, interferences and compensations between the different strategies Si. This interplay takes into account all the constraints both external (preservation of physical laws) and internal (structural temporal constraints of the CRs), as well as possible ponderations of the strategies Sito minimize the global cost for the system.

In this process, some of the strategies may fail, causing a fracture in the corresponding CRs. Let us remark that fractures can appear even if all the strategies are compatible, if the CR has not well evaluated the situation (breakage of stock because of a bad management).

Two CRs, let us call them a macroCR and a microCR, are heterogeneous if the macroCR has its complexity level greater than that of the microCR and its period much longer than the period of the microCR. These CRs form very different landscapes and the realization of their strategies require variable delays. During a unique step of the macroCR there will be a sequence of successive steps of the microCR, each one causing modifications of which the macroCR will not be informed in real time because of the propagation delays. The resulting changes may later affect the realization of the strategy of the macroCR, with a risk of fracture in its macrolandscape. For instance the macrostrategy can require to bind together objects some of which have been suppressed through the intermediate strategies of the microCR.

To repair the fracture the macroCR must change its strategy, possibly with a modification of its period to maintain its structural temporal constraints; the role of the fracture may be creative if it imposes a complete review of the situation leading to the formation of a more powerful new strategy. And this might have consequences for the whole system, with possible later repercussions for the microCR.

Generally in self-organized natural systems, the strategies of the lower CRs are pre-eminent on the short term, since the behavior of a complex object is directed by that of its components acting synergetically. But these CRs are directly or indirectly controlled by higher CRs with longer periods which may impose their strategies on the long term, either to disentangle an obstruction, or to avoid or repair a fracture at their own level. And the process is iterated to higher and higher levels. Roughly, macrochanges occur more slowly, but are more serious for the whole system. For instance, slow changes in a society are not always perceived in time by the government, whence revolutions which impose a deep change in the society.

This dialectics between heterogeneous CRs characterizes the behavior of a complex system and shows that any approximation (or simulation) by a 'simple' physical system is only valid 'locally and temporarily' (as suggested by Rosen). Indeed,usual models based on differential equations (or dynamical systems) could describe one particular complexification process because it is entirely determined by the initial state and the strategy (which gives the parameters). But they could not describe a non-reducible sequence of complexifications, in which higher order objects emerge at each step.